A study of 975 older adults (ages 60-80) with hypertension showed that about 40 percent were able to maintain diet and exercise changes, enabling many to stop taking medication for high blood pressure.
"One of the remarkable things about this study is that people maintained their weight loss or low-sodium diet for at least two and a half years," said Walter H. Ettinger Jr., M.D., M.B.A., who headed the study at Wake Forest.
Ettinger said there had been skepticism that people could not stick to diets, since the typical pattern is for people to gain weight back soon after losing it.
A 1991 report by the National Institutes of Health states, "There is a strong tendency to regain weight, with a much as two-thirds of the weight loss regained within one year." In one study of one commercial diet program, only 12 percent of 192 participants managed to maintain at least 75 percent of their weight loss three years after the program.
"The finding that older patients with hypertension were able to make and sustain lifestyle changes suggests that health habits can be changed, even if they've been practiced over many years," said Ettinger.
Positive changes in diet and exercise have been associated with better control of diabetes, reduced risk of cardiovascular disease, and improved symptoms of osteoarthritis, chronic obstructive lung disease and congestive heart failure.
Another significant finding from the TONE study (Trial of Nonpharmacologic Interventions in the Elderly) was that moderate changes in body weight and salt intake (losing just 10 pounds of body weight and restricting dietary salt to 1,800 mg. a day) resulted in impressive results -- the ability to control blood pressure without medication.
"Either weight loss or control of dietary salt were fairly effective substitutes for medication for up to half the participants," said Mark Espeland, Ph.D., director of the TONE coordinating center.
The TONE study randomly assigned overweight participants to one of four groups: usual care, reduction of sodium, weight loss, or both sodium reduction and weight loss. Participants who had normal body weight got either usual care or were placed in a sodium reduction group.
Participants met with diet and exercise counselors who were experienced in techniques for lifestyle changes. During the first four months, counselors met with participants weekly, either individually or in groups, and advised them of ways to change eating patterns and increase physical activity.
During the next four months, twice-a-month meetings focused on problem solving and relapse. Next, the counselors focused on keeping the participants motivated, especially those who were less active in practicing the behavior change techniques.
At the 30-month follow-up, 35 percent of participants in the sodium reduction group continued to meet the goal of limiting salt to 1,800 mg. per day and 44 percent of those in the weight loss group had maintained their loss of 10 or more pounds.
At an average of 90 days after the first intervention session, participants were withdrawn from their blood pressure medications. About four out of 10 people (39 percent) in the weight loss group or the sodium group (38 percent) were successfully off medications 2 years later, when the study ended.
The researchers believe that the participants were more successful than most people at maintaining lifestyle changes because they were highly motivated to get off blood pressure medicine, which is expensive and can have side effects.
Earlier studies had demonstrated that reducing weight or controlling sodium could effectively replace medication in younger age groups. TONE was the first study of sufficient length and size to provide convincing evidence regarding lifestyle changes as a way to control high blood pressure in older adults.
In addition to Wake Forest University Baptist Medical Center, Johns Hopkins, the University of Tennessee in Memphis, and the Robert Wood Johnson Medical School in New Jersey conducted the multi-center study, which was funded by the National Institutes of Health.
Contact: Karen Richardson, (336) 716-4453 or Jim Steele, (336) 716-3487.
Journal
JAMA